arXiv subjects
Publications and source records attributed to Paul Turcotte.
We derive a simple analytic expression for q \bar{q}, g g -> t \bar{t} -> b W^+ \bar{b} W^- -> b \bar{l} ν_l \bar{b} l' \bar{ν_{l'}} for on shell intermediate states with the interference effects due to the polarizations of the t and \bar{t}. We then investigate how this effect may be measured at Tevatron or other hadronic colliders.
Using the recent CLEO measurement of $Br(b\to s γ)$, we find that the branching ratio of $b\to s g$ cannot be larger than $10\%$ in two Higgs doublet models. The small experimental value of $Br(b\to e\barνX)$ can no longer be explained by charged Higgs boson effects.
Allowing for realistic uncertainties in input parameters, we demonstrate that the present CLEO limit of $5.4\times 10^{-4}$ for inclusive $b\to sγ$ decay does not yet fully exclude the $t\to bH^+$ decay possibility in supersymmetric type of two Higgs doublet models. Combined with direct search for $t\to bH^+$ via $H^+\to τ^+ν$ at the Tevatron, we conclude that $\tanβ\sim 1$ is the ``allowed" window for $m_{H^+} < m_t < M_W$. The possibility becomes excluded, however, {\it if} the CLEO limit is pushed below $4\times 10^{-4}$.